Chair back



FIG. 1 is a front perspective view of a chair back;

FIG. 2 is a rear perspective view of a chair back;

FIG. 3 is a right side elevation view of a chair back;

FIG. 4 is a front elevation view of a chair back;

FIG. 5 is a left side elevation view of a chair back;

FIG. 6 is a rear elevation view of a chair back;

FIG. 7 is a top plan view of a chair back;

FIG. 8 is a bottom plan view of a chair back;

FIG. 9 is a front perspective view of a second embodiment of a chair back;

FIG. 10 is a rear perspective view of a second embodiment of a chair back;

FIG. 11 is a right side elevation view of a second embodiment of a chair back;

FIG. 12 is a front elevation view of a second embodiment of a chair back;

FIG. 13 is a left side elevation view of a second embodiment of a chair back;

FIG. 14 is a rear elevation view of a second embodiment of a chair back;

FIG. 15 is a top plan view of a second embodiment of a chair back; and,

FIG. 16 is a bottom plan view of a second embodiment of a chair back.

In the drawings, the broken lines depict environmental subject matter only and form no part of the claimed design. 

The ornamental design for a chair back, as shown and described. 